Buggy code:
protected static final int K_INSIDE_ASSERT_STATEMENT = ( CompletionParser . COMPLETION_PARSER ) + 24 ; protected static final int K_SWITCH_LABEL = ( CompletionParser . COMPLETION_PARSER ) + 25 ; protected static final int K_BETWEEN_CASE_AND_COLON = ( CompletionParser . COMPLETION_PARSER ) + 26 ; protected static final int K_BETWEEN_DEFAULT_AND_COLON = ( CompletionParser . COMPLETION_PARSER ) + 27 ; protected static final int K_BETWEEN_LEFT_AND_RIGHT_BRACKET = ( CompletionParser . COMPLETION_PARSER ) + 28 ; protected static final int K_EXTENDS_KEYWORD = ( CompletionParser . COMPLETION_PARSER ) + 29 ; protected static final int K_PARAMETERIZED_METHOD_INVOCATION = ( CompletionParser . COMPLETION_PARSER ) + 30 ; protected static final int K_PARAMETERIZED_ALLOCATION = ( CompletionParser . COMPLETION_PARSER ) + 31 ; protected static final int K_PARAMETERIZED_CAST = ( CompletionParser . COMPLETION_PARSER ) + 32 ; protected static final int K_BETWEEN_ANNOTATION_NAME_AND_RPAREN = ( CompletionParser . COMPLETION_PARSER ) + 33 ; public static final char [ ] FAKE_TYPE_NAME = new char [ ] { '<seq2seq4repair_space>' } ; public static final char [ ] VALUE = new char [ ] { 'v' , 'a' , 'l' , 'u' , 'e' } ; public int cursorLocation ; public ASTNode assistNodeParent ; static final int IF = 1 ; static final int TRY = 2 ; static final int CATCH = 3 ; static final int WHILE = 4 ; static final int SWITCH = 5 ; static final int FOR = 6 ; static final int DO = 7 ; static final int SYNCHRONIZED = 8 ; static final int DEFAULT = 1 ; static final int EXPLICIT_RECEIVER = 0 ; static final int NO_RECEIVER = - 1 ; static final int SUPER_RECEIVER = - 2 ; static final int NAME_RECEIVER = - 3 ; static final int ALLOCATION = - 4 ; static final int QUALIFIED_ALLOCATION = - 5 ; static final int QUESTION = 1 ; static final int COLON = 2 ; static final int LPAREN_NOT_CONSUMED = 1 ; static final int LPAREN_CONSUMED = 2 ; int invocationType ; int qualifier ; int lastModifiers = AccDefault ; int lastModifiersStart = - 1 ; int bracketDepth ; int canBeExplicitConstructor = CompletionParser . NO ; static final int NO = 0 ; static final int NEXTTOKEN = 1 ; static final int YES = 2 ; boolean isAlreadyAttached ; public CompletionParser ( ProblemReporter problemReporter ) { } public char [ ] assistIdentifier ( ) { } protected void attachOrphanCompletionNode ( ) { } private void buildMoreAnnotationCompletionContext ( MemberValuePair memberValuePair ) { } private void buildMoreCompletionContext ( Expression expression ) { Statement statement = expression ; int kind = topKnownElementKind ( CompletionParser . COMPLETION_OR_ASSIST_PARSER ) ; if ( kind != 0 ) { int info = topKnownElementInfo ( CompletionParser . COMPLETION_OR_ASSIST_PARSER ) ; nextElement : switch ( kind ) { case CompletionParser . K_SELECTOR_QUALIFIER : int selector = topKnownElementInfo ( CompletionParser . COMPLETION_OR_ASSIST_PARSER , 2 ) ; if ( ( selector == ( AssistParser . THIS_CONSTRUCTOR ) ) || ( selector == ( AssistParser . SUPER_CONSTRUCTOR ) ) ) { ExplicitConstructorCall call = new ExplicitConstructorCall ( ( selector == ( AssistParser . THIS_CONSTRUCTOR ) ? ExplicitConstructorCall . This : ExplicitConstructorCall . Super ) ) ; call . arguments = new Expression [ ] { expression } ; call . sourceStart = expression . sourceStart ; call . sourceEnd = expression . sourceEnd ; assistNodeParent = call ; } else { int invocType = topKnownElementInfo ( CompletionParser . COMPLETION_OR_ASSIST_PARSER , 1 ) ; int qualifierExprPtr = info ; int length = expressionLengthStack [ expressionLengthPtr ] ; <START_BUG> if ( ( ( expressionLengthPtr ) > 0 ) && ( length == 1 ) ) { <END_BUG> int start = ( ( int ) ( ( identifierPositionStack [ selector ] ) > > > 32 ) ) ; if ( ( ( this . expressionStack [ ( ( expressionPtr ) - 1 ) ] ) != null ) && ( ( this . expressionStack [ ( ( expressionPtr ) - 1 ) ] . sourceStart ) > start ) ) { length += expressionLengthStack [ ( ( expressionLengthPtr ) - 1 ) ] ; } } Expression [ ] arguments = null ; if ( length != 0 ) { arguments = new Expression [ length ] ; expressionPtr -= length ; System . arraycopy ( expressionStack , ( ( expressionPtr ) + 1 ) , arguments , 0 , ( length - 1 ) ) ; arguments [ ( length - 1 ) ] = expression ; } if ( ( invocType != ( CompletionParser . ALLOCATION ) ) && ( invocType != ( CompletionParser . QUALIFIED_ALLOCATION ) ) ) { MessageSend messageSend = new MessageSend ( ) ; messageSend . selector = identifierStack [ selector ] ; messageSend . arguments = arguments ; switch ( invocType ) { case CompletionParser . NO_RECEIVER : messageSend . receiver = ThisReference . implicitThis ( ) ; break ; case CompletionParser . NAME_RECEIVER : while ( ( ( this . identifierLengthPtr ) >= 0 ) && ( ( this . identifierLengthStack [ this . identifierLengthPtr ] ) < 0 ) ) { ( this . identifierLengthPtr ) -- ; } ( this . identifierPtr ) -- ; ( this . identifierLengthStack [ this . identifierLengthPtr ] ) -- ; int identifierLength = this . identifierLengthStack [ this . identifierLengthPtr ] ; if ( ( ( ( this . identifierPtr ) > ( - 1 ) ) && ( identifierLength > 0 ) ) && ( ( ( this . identifierPtr ) + 1 ) >= identifierLength ) ) { messageSend . receiver = this . getUnspecifiedReference ( ) ; } else { messageSend = null ; } break ; case CompletionParser . SUPER_RECEIVER : messageSend . receiver = new SuperReference ( 0 , 0 ) ; break ; case CompletionParser . EXPLICIT_RECEIVER : messageSend . receiver = this . expressionStack [ qualifierExprPtr ] ; break ; default : messageSend . receiver = ThisReference . implicitThis ( ) ; break ; }

Fix:
if ( ( ( ( this . expressionPtr ) > 0 ) && ( ( this . expressionLengthPtr ) > 0 ) ) && ( length == 1 ) ) {